The present invention relates to an aortic catheter for inducing cardioplegic arrest and for segmenting and selectively perfusing the aorta during cardiopulmonary bypass.
Recent advances in the field of minimally invasive cardiac surgery have included the development of aortic catheters and methods for inducing cardioplegic arrest without the necessity of opening the patient""s chest with a sternotomy or other major thoracotomy. For example, U.S. Pat. Re No. 35,352 to Peters describes a single balloon catheter for occluding a patient""s ascending aorta and a method for inducing cardioplegic arrest. A perfusion lumen or a contralateral arterial cannula is provided for supplying oxygenated blood during cardiopulmonary bypass. U.S. Pat. No. 5,584,803 to Stevens et al. describes a single balloon catheter for inducing cardioplegic arrest and a system for providing cardiopulmonary support during closed chest cardiac surgery. A coaxial arterial cannula is provided for supplying oxygenated blood during cardiopulmonary bypass. The occlusion balloon of these catheters must be very carefully placed in the ascending aorta between the coronary arteries and the brachiocephalic artery, therefore the position of the catheter must be continuously monitored to avoid complications. In clinical use, these single balloon catheters have shown a tendency to migrate in the direction of the pressure gradient within the aorta. That is to say that, during infusion of cardioplegia, the balloon catheter will tend to migrate downstream due to the higher pressure on the upstream side of the balloon and, when the CPB pump is on, the balloon catheter with tend to migrate upstream into the aortic root due to the higher pressure on the downstream side of the balloon. This migration can be problematic if the balloon migrates far enough to occlude the brachiocephalic artery on the downstream side or the coronary arteries on the upstream side. PCT patent application WO 9721462 by Fan et al. attempts to overcome this problem with a balloon catheter having high friction areas on the outer surface of the balloon. A problem with this single balloon approach is that a relatively large balloon is needed to create enough friction to avoid migration of the inflated balloon. The larger the balloon is, the more carefully it must be placed in the ascending aorta to avoid occluding the coronary arteries or the brachiocephalic artery and the less margin of error there is should any balloon migration occur.
U.S. Pat. No. 5,312,344 to Grinfeld et al. describes an arterial perfusion cannula having two closely spaced balloons positioned in the ascending aorta. However, this patent does not provide any guidance on how to avoid migration or inadvertent occlusion of the coronary arteries or the brachiocephalic artery. It would be desirable to provide an aortic occlusion catheter for inducing cardioplegic arrest that minimizes the likelihood of migration of the balloon or occluding member in the ascending aorta.
Another important development in the area of aortic balloon catheters is the concept of selective aortic perfusion. U.S. Pat. Nos. 5,308,320, 5,383,854 and 5,820,593 by Peter Safar, S. William Stezoski and Miroslav Klain describe a double balloon catheter for segmenting a patient""s aorta for selective perfusion of different organ systems within the body. Other U.S. patents which address the concept of selective aortic perfusion include U.S. Pat. Nos. 5,738,649, 5,833,671 and 5,827,237 by John A. Macoviak; and Michael Ross and commonly owned, copending patent applications; Ser. No. 08/909,293 filed Aug. 11, 1997; and Ser. No. 08/909,380 filed Nov. 8, 1997, by Safar et al.; and Ser. No. 08/665,635, filed Jun. 18, 1996; by John A. Macoviak; and Michael Ross. These patent applications and all other patents referred to herein are hereby incorporated by reference in their entirety. Selective perfusion can be used to prioritize the flow of oxygenated blood or other protective fluids to the various organ systems, therefore achieving optimal preservation of all organ systems within the body. It would be desirable to include this feature of selective perfusion in an aortic occlusion catheter for inducing cardioplegic arrest.
Accordingly, the present invention provides an aortic catheter having an upstream occlusion member positioned in the ascending aorta between the coronary arteries and the brachiocephalic artery and a downstream anchoring member positioned in the descending aorta, downstream of the aortic arch. The upstream occlusion member may be an inflatable balloon or a selectively deployable external catheter valve. Preferably, the upstream occlusion member is narrow enough in construction that it is easily placed between the coronary arteries and the brachiocephalic artery without any danger of inadvertently occluding either. The downstream anchoring member may be a larger inflatable balloon or other anchoring structure that provides sufficient friction to prevent migration of the balloon catheter in the upstream or downstream direction. Preferably, the upstream occlusion member and the downstream anchoring member are mounted on an elongated catheter shaft, which includes lumens for inflating or otherwise actuating the occlusion member and the anchoring member and a lumen or lumens for perfusion of the aorta with oxygenated blood or other fluids. The catheter may be configured for retrograde deployment via a peripheral artery, such as the femoral artery, or it may be configured for antegrade deployment via an aortotomy incision or direct puncture in the ascending aorta.
A first embodiment of the aortic catheter of the present invention is described, which is configured for retrograde deployment via a peripheral artery, such as the femoral artery. The aortic catheter has an elongated catheter shaft having a proximal end and a distal end. An upstream occlusion member, in the form of an inflatable balloon, is mounted on the catheter shaft near the distal end of the catheter shaft so that it is positioned in the ascending aorta when deployed. A larger inflatable balloon, which serves as a downstream anchoring member, is mounted at a position proximal to the upstream occlusion member so that it is positioned in the descending aorta when deployed. A corporeal perfusion lumen extends through the catheter shaft from the proximal end to one or more corporeal perfusion ports on the exterior of the catheter shaft proximal of the downstream anchoring member. An arch perfusion lumen extends through the catheter shaft from the proximal end to one or more arch perfusion ports on the exterior of the catheter shaft between the upstream occlusion member and the downstream anchoring member. An arch pressure lumen extends through the catheter shaft from the proximal end to an arch pressure port located between the upstream occlusion member and the downstream anchoring member to monitor pressure in the aortic arch. A common balloon inflation lumen extends through the catheter shaft from the proximal end to balloon inflation ports within the upstream occlusion member and the downstream anchoring member. A root pressure lumen extends through the catheter shaft from the proximal end to a root pressure port near the distal end of the catheter shaft to monitor pressure in the aortic root. A guide wire and cardioplegia lumen extends from the proximal end of the catheter shaft to the distal end, distal to the upstream occlusion member.
A second embodiment of the aortic catheter is described, which is also configured for retrograde deployment via a peripheral artery, such as the femoral artery. The aortic catheter has an elongated catheter shaft having a proximal end and a distal end. An upstream occlusion member, in the form of an inflatable balloon, is mounted on the catheter shaft near the distal end of the catheter shaft so that it is positioned in the ascending aorta when deployed. A larger inflatable balloon, which serves as a downstream anchoring member, is mounted at a position proximal to the upstream occlusion member so that it is positioned in the descending aorta when deployed. An arch perfusion lumen extends through the catheter shaft from the proximal end to one or more arch perfusion ports on the exterior of the catheter shaft between the upstream occlusion member and the downstream anchoring member. An arch pressure lumen extends through the catheter shaft from the proximal end to an arch pressure port located between the upstream occlusion member and the downstream anchoring member to monitor pressure in the aortic arch. A common balloon inflation lumen extends through the catheter shaft from the proximal end to balloon inflation ports within the upstream occlusion member and the downstream anchoring member. A root pressure lumen extends through the catheter shaft from the proximal end to a root pressure port near the distal end of the catheter shaft to monitor pressure in the aortic root. A guide wire and cardioplegia lumen extends from the proximal end of the catheter shaft to the distal end, distal to the upstream occlusion member. A separate contralateral or coaxial arterial cannula would be used with this embodiment of the aortic catheter to supply oxygenated blood to the corporeal circulation.
A third embodiment of the aortic catheter of the present invention is described, which is configured for antegrade deployment via an aortotomy or direct aortic puncture. The aortic catheter has an elongated catheter shaft having a proximal end and a distal end. Because the catheter is configured for antegrade deployment, the proximal and distal positions of many of the features of the catheter are reversed with respect to the retrograde embodiments previously described. A downstream anchoring member, in the form of a large inflatable balloon, is mounted on the catheter shaft near the distal end of the catheter shaft so that it is positioned in the descending aorta when deployed. An upstream occlusion member, in the form of an inflatable balloon, is mounted at a position proximal to the downstream anchoring member so that it is positioned in the ascending aorta when deployed. An arch perfusion lumen extends through the catheter shaft from the proximal end to one or more arch perfusion ports on the exterior of the catheter shaft between the upstream occlusion member and the downstream anchoring member. An arch pressure lumen extends through the catheter shaft from the proximal end to an arch pressure port located between the upstream occlusion member and the downstream anchoring member to monitor pressure in the aortic arch. A common balloon inflation lumen extends through the catheter shaft from the proximal end to balloon inflation ports within the upstream occlusion member and the downstream anchoring member. A guide wire and corporeal perfusion lumen extends from the proximal end of the catheter shaft to the distal end, distal to the downstream anchoring member. A separate cardioplegia needle or catheter would be used with this embodiment of the aortic catheter to infuse cardioplegia fluid into the aortic root upstream of the upstream occlusion member.
A fourth embodiment of the aortic catheter, configured for retrograde deployment, is described wherein the upstream occlusion member is in the form of a narrow, disk shaped balloon. A fifth embodiment of the aortic catheter, configured for antegrade deployment, is described wherein the upstream occlusion member is in the form of a narrow, disk shaped balloon.
A sixth embodiment of the aortic catheter, configured for retrograde deployment, is described wherein the upstream occlusion member is in the form of a selectively deployable peripheral flow external catheter valve. A seventh embodiment of the aortic catheter, also configured for retrograde deployment, is described wherein the upstream occlusion member is in the form of a selectively deployable central flow external catheter valve. An eighth embodiment of the aortic catheter, configured for retrograde deployment, is described wherein the downstream anchoring member is in the form of two inflatable balloons.
Methods according to the present invention are described using the aortic catheter for occluding the ascending aorta and for inducing cardioplegic arrest, for supporting the patient""s circulation on cardiopulmonary bypass, for partitioning the patient""s aorta and for performing selective aortic perfusion.